The present invention relates to an improvement in a multicoordinate sensing head of the type having a housing, a sensing pin, means for mounting the pin in the housing such that the pin is deflectable in a plurality of directions and is returned to a predetermined rest position following deflection, and means for generating a deflection signal in response to deflection of the pin.
A number of publications disclose a large diversity of multicoordinate sensing heads.
Thus, for example, German Patent DE-PS No. 22 42 355 discloses an electronic multicoordinate sensor, the sensing pin of which is mounted on a special straight guidance system. The disclosed multicoordinate sensor includes signal generators which operate to generate a deflection signal in response to the deflection of the sensing pin.
Furthermore, German DE-OS No. 15 48 326 shows a prior art zero sensing system adapted to be used on machine tools, in which an overload protection system is provided which in case of an overload allows a separation of the zero sensing system and the measuring device.
The foregoing examples of the prior art have been selected from a large number of relevant publications only by way of example. These prior art devices exhibit shortcomings when they are used not only in connection with measuring machines, but also to an increasing degree in connection with numerically controlled processing machines, such as processing centers. Workshop operation provides a harsh environment for multicoordinate sensors in contrast to the controlled environment of the measuring room. If efficiency and dependability of operation are to be maximized, largely automatic manufacturing machines will require measuring systems of a type different from known prior art approaches.